def test1():
    l = []
    for i in range(1000):
       l = l + [i]

def test2():
   l = []
   for i in range(1000):
      l.append(i)
def test3():
    l = [i for i in range(1000)]

def test4():
   l = list(range(1000))

from timeit import Timer

t1 = Timer("test1()", "from __main__ import test1")

print("concat ",t1.timeit(number=1000), "seconds")

t2 = Timer("test2()", "from __main__ import test2")

print("append ",t2.timeit(number=1000), "seconds")

t3 = Timer("test3()", "from __main__ import test3")

print("comprehension ",t3.timeit(number=1000), "seconds")

t4 = Timer("test4()", "from __main__ import test4")

print("list range ",t4.timeit(number=1000), "seconds")

